Classes and continua of hippocampal CA1 inhibitory neurons revealed by single-cell transcriptomics

摘要: Understanding any brain circuit will require a categorization of its constituent neurons. In hippocampal area CA1, at least 23 classes GABAergic neuron have been proposed to date. However, this list may be incomplete; additionally, it is unclear whether discrete are sufficient describe the diversity cortical inhibitory neurons, or continuous modes variability also required. We studied transcriptomes 3663 CA1 cells, revealing 10 major groups that divided into 49 fine-scale clusters. All previously described and several novel cell were identified, with three previously-described unexpectedly found identical. A common mode variation modulated expression many genes, reflecting range from metabolically highly active faster-spiking cells proximally target pyramidal slower-spiking distal dendrites interneurons. Within classes, showed further along continuum correlated their spiking phenotype. Surprisingly, types as represented ranges continuum. These results elucidate complexity neurons in one simplest structures, show characterizing these requires well classes.